Apparatuses and methods for rsrp measurements for a wireless device with variable output power per antenna arrangement

ABSTRACT

When a TRP performs a TRP beam sweep for a WD with multiple antenna arrangements and the WD is expected to perform an UL transmission (e.g., the WD has at least a threshold amount of data in its transmit buffer) and UL beam selection is based on DL beam selection, in one embodiment the WD takes the available output power of the different antenna arrangements in to account during RSRP calculations for the different candidate TRP TX beams such that the RSRP from an antenna arrangement that has lower available output power is weighted less compared to the RSRP measured from an antenna arrangement that has higher available output power.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.16/347,076, filed on May 2, 2019, which is a national stage entry ofPCT/EP2019/053745, filed on Feb. 14, 2019. The above identifiedapplications are incorporated by this reference.

TECHNICAL FIELD

This disclosure relates to apparatuses and methods for reference signalreceived power (RSRP) measurements.

BACKGROUND

Beam Management

Narrow beam transmission and reception schemes are typically needed athigher frequencies to compensate for high propagation loss. For a givencommunication link, a beam can be applied at both the transmit/receivepoint (TRP) (i.e., an access point, such as a base station, or acomponent of an access point) and a wireless device (WD), which will bereferred to as a beam pair link (BPL) in this disclosure. As used hereina WD is a communication device (mobile or stationary) that is capable ofwireless communication with a TRP (examples of WDs includes:smartphones, smart appliances, Cellular Internet-of-Things (CIoT)devices, etc.).

A beam management procedure is employed to discover and maintain a TRP104 beam 112 (e.g., a TRP transmit (TX) beam) and/or a WD 102 beam 116(e.g., a WD receive (RX) beam). In the example of FIG. 1, one BPL hasbeen discovered (i.e., the beam pair that consists of TRP beam 112 andWD beam 116) and is being maintained by the network. A BPL is expectedto mainly be discovered and monitored by the network using measurementson downlink (DL) reference signals (RSs) used for beam management, e.g.,CSI-RS (channel-state-information RS). The CSI-RS for beam managementcan be transmitted periodically, semi-persistently or aperiodic (eventtriggered) and they can be either shared between multiple WDs or beWD-specific. In order to find a suitable TRP TX beam the TRP 104transmits CSI-RS in different TRP TX beams on which the WD 102 performsRSRP measurements and reports back the N best TRP TX beams (where N canbe configured by the network). Furthermore, the CSI-RS transmission on agiven TRP TX beam can be repeated to allow the WD to evaluate suitableWD beam (WD RX beam training). Which RX beam the WD chooses will beagnostic to the TR in NR, hence there is no need for the WD to signalback to the TRP the RX beam chosen by the WD.

It is expected that the determination of a BPL between a TRP and WD(i.e. finding a suitable TRP beam and WD beam) starts with a P2 beamsweep (illustrated in FIG. 2A), which means that the TRP transmitsCSI-RS in different TRP beams 203 and the WD measures RSRP using a fixedWD RX beam 201 for each of its antenna panels (only one is shown in thisexample) and signals back the CSI-RS resource index(s) (CRI(s))corresponding to the highest RSRP(s) (the WD has to report the TRPbeam(s) with highest RSRP according the standard and there might be RAN4tests that check that the WD follow this). During such P2 beam sweep itis expected that the WD will apply as wide beam as possible of each WDpanel such that as many propagation paths as possible between the TRPand the WD can be evaluated during the P2 beam sweep.

In the next step the TRP is expected to do a P3 beam sweep (illustratedin FIG. 2B), where the TRP transmits a burst of CSI-RS in (typically)the best reported TRP TX beam from the P2 procedure (beam 250 in theexample shown in FIG. 2B), which means that the WD can sweep throughdifferent WD RX beams 205, perform measurements on the CSI-RS and selecta preferred WD RX beam (e.g., beam 251). How the WD determine thecandidate WD RX beams is up to WD implementation. As long as both theTRP and WD has beam correspondence, it is expected that the same BPL(i.e. the same TRP beam and WD beam) also will be used for UL.

WD Antenna Implementation

For UEs, the incoming signals can arrive from many different directions.Accordingly, it is beneficial to have an antenna implementation at theWD which has the possibility to generate omni-directional-like coveragein addition to high gain narrow beams. One way to increase theomni-directional coverage at a WD is to install multiple panels, andpoint the panels in different directions, as schematically illustratedin FIG. 3 for a WD 302 with two panels.

It is also possible that the WD is not equipped with antenna panels, butfor example instead has directional antennas pointing in differentdirections as schematically illustrated in FIG. 4, for a WD 402 withfour antennas (411, 412, 413, and 414) pointing in different directions.

Different Output Power for Different WD Antenna Arrangements

A WD equipped with multiple antenna arrangements (e.g., antenna panelsor antennas) might have different available power to transmit from thedifferent arrangements. For example, it has been agreed in 3GPP that NRshould support three different categories of UEs: 1) UEs that cantransmit with full output power for each of the WD TX chains, 2) UEsthat can transmit with full output power for only a subset of all the WDTX chains, and 3) UEs that cannot transmit with full output power on anyof the WD TX chains. Especially for alternative 2), different WD antennaarrangements will have different maximum allowed output power.

Also, it is currently a discussion in 3GPP about restricting WD outputpower for certain WD TX beams that transmits power in directions towardssensitive objects, like for example a human body. It is possible that asubset of the UEs antenna arrangements are transmitting in a directionof a sensitive object and therefore have to reduce the maximum allowedoutput power, hence, in this case, different WD antenna arrangement willhave different maximum allowed output power.

Furthermore, a WD equipped with multiple antenna arrangements might turnoff the transmitter chain for a subset of the arrangements while stillkeeping all receiver chains active. The arrangements with turned off TXchains can be considered to have zero transmission power, while thearrangements that still have active TX chains have a higher potentialoutput power, hence one can say that the transmission power will differfor different arrangements at the WD for this scenario.

SUMMARY

Certain challenges presently exist. During a TRP TX beam sweep (e.g., a3GPP P2 beam management procedure), the WD should measure the RSRP forthe different candidate TRP TX beams and report the N beams with highestRSRP. If beam correspondence is fulfilled at both the TRP and WD, itexpected that the TRP will configure the WD with UL transmission in thesame BPL as is used for DL transmission. When the WD has multipleantenna arrangements, the straightforward solution for calculating theRSRP would be to just calculate RSRP for each CSI-RS resource (i.e., foreach TRP TX beam) for each WD antenna arrangement, and then take alinear average of the multiple RSRP values to get the resulting RSRPvalue (for each TRP TX beam). This, however, might lead to sub-optimalrecommendations of TRP TX beams w.r.t the WD UL transmission, since theBPL determined in this way might depend on an antenna arrangement withsignificantly lower output power (or even zero output power if thetransmit chain is turned off).

To overcome this problem, when a TRP performs a TRP TX beam sweep for aWD with multiple antenna arrangements, in one particular embodiment, ifthe WD is expected to perform an UL transmission (e.g., the WD has atleast a threshold amount of data in its transmit buffer) and zero ormore other conditions are met, then the WD will take the availableoutput power of the different antenna arrangements in to account duringRSRP calculations for the different TRP TX beams such that the RSRP froman antenna arrangement that has lower available output power is weightedless compared to the RSRP measured from an antenna arrangement that hashigher available output power.

Accordingly, in one aspect there is provided a process performed by a WDfor selecting candidate TX beams included in a set of candidate TX beamsincluding at least a first candidate TX beam b1. The WD includes a firstantenna arrangement (AA1), a second antenna arrangement (AA2), and anuplink (UL) transmit buffer. The process includes determining a firstuplink transmit power (TP1) for the AA1 and determining a second uplinktransmit power (TP2) for AA2. The process also includes using the AA1 toreceive a reference signal transmitted by a base station using the firstcandidate TX beam. The process also includes obtaining, based on thereference signal transmitted by the base station using the firstcandidate TX beam and received using AA1, a first received referencesignal power value (P11) associated with AA1. The process also includesusing AA2 to receive the reference signal transmitted by the basestation using the first candidate TX beam. The process also includesobtaining, based on the reference signal transmitted by the base stationusing the first candidate TX beam and received using AA2, a secondreceived reference signal power value (P12) associated with AA2. Theprocess also includes determining a final reference signal receivedpower value (Pn1) for the first candidate TX beam using P11 and P12 andfurther using TP1, TP2, information indicating an amount of data in theuplink transmit buffer, an estimate of an UL link budget, and/orinformation indicating whether or not UL beam selection is determinedbased on DL beam selection. The process also includes using Pn1 toassign a rank to the first candidate TX beam. The process also includesdetermining, based on the rank assigned to the first candidate TX beam,whether or not to include in a beam report a beam indicator (e.g., aCRI) indicating the first candidate TX beam. The process furtherincludes transmitting the beam report to the base station, wherein thebeam report includes at least one beam indicator indicating at least onecandidate TX beam.

An advantage of the above described embodiment is that the TRP TX beamcan be selected taking the UL performance in to account, which will makeit possible for the WD to balance the UL and DL performance in anoptimal way.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated herein and form partof the specification, illustrate various embodiments.

FIG. 1 illustrates a conventional beam-pair link (BPL).

FIG. 2A illustrates a P2 beam sweep for identifying a best TRP TX beam.

FIG. 2B illustrates a P3 beam sweep for identifying a best WD RX beam.

FIG. 3 illustrates a WD being equipped with at least two antenna panels.

FIG. 4 illustrates a WD being equipped with directional antennaspointing in different directions.

FIG. 5 is an example message flow diagram illustrating a processaccording to an embodiment.

FIG. 6 illustrates a TRP communicating with a WD.

FIG. 7 is a flow chart illustrating a process according to anembodiment.

FIG. 8 is a block diagram of an apparatus according to one embodiment.

DETAILED DESCRIPTION

FIG. 5 is a message flow diagram illustrating a process according to anembodiment. In step s502, WD 502 determines the available output powerfor each of its antenna arrangements. For this example, we will assumethat WD 502 has two antenna arrangements: a first antenna arrangementAA1 and a second antenna arrangement AA2 (see FIG. 6). Accordingly, inthis example WD 502 determines TP1 (the available output power for thefirst antenna arrangement—a.k.a., first UL transmit power) anddetermines TP2 (the available output power for the second antennaarrangement—a.k.a., second UL transmit power).

In some embodiments, the WD determines the available UL transmit powerfor each antenna arrangement based solely on the power amplifier (PA)implementation at the WD, which is known to the WD. In anotherembodiment, the WD determines if any candidate uplink (UL) TX beam fromthe different WD antenna arrangements hits a human body (which may forexample be detected by using proximity censors, accelerometers, camerasetc), and based on that information determines the available outputpower of the different antenna arrangements. In yet another embodiment,for each antenna arrangement at the WD, the WD determines if the TXchain is turned off for the antenna arrangement, and in this waydetermines that the available output power for that antenna arrangementwould be zero. If panel, antenna, and or beam-specific power control isused, each antenna arrangements may be associated with a different openloop and/or closed loop power control mechanism. In that case, suchinformation may also be utilized to determine the available output powerfor the different WD antenna arrangements.

In step s504, the serving TRP 504 initiates a P2 beam sweep and thenperforms the sweep by transmitting CSI-RS using the different candidateTRP TX beams (in this example we will assume that the set of candidateTRP TX beams consists of two different TRP TX beams: beam b1 and beam b2(see FIG. 6)). In the example illustrated in FIG. 5, there are at leasttwo different CSI-RS transmission, one for each of the two candidate TRPTX beams. In some embodiments, initiating the P2 beam sweep includes theTRP 504 sending to WD 502 a unique CSI-RS resource indicator (CRI) foreach of the candidate TRP TX beams. Each CRI identifies to WD 502 theresources (e.g., time-frequency resources) that TRP 504 will use whenthe TRP 504 uses the TX beam corresponding to the CRI to transmit theCSI-RS. In this way, WD 504 can map the reception of a CSI-RS to aspecific candidate TRP TX beam as the CRI functions as a beam indicator.

In step s506, WD 502 determines an RSRP value for each of the twocandidate TRP TX beams based on the CSI-RS transmissions. As describedabove, a straightforward solution would be to just calculate, for eachCIS-RS resource (i.e., each TRP TX beam), two RSRP values (one for eachantenna arrangement) and then take the linear average of the two RSRPvalues to get a final RSRP value for the candidate TRP TX beam. However,this might lead to sub-optimal recommendations of TRP TX beams w.r.t. ULperformance since the selected BPL for downlink might depend on a WDantenna arrangement that as limited output power in UL (or even zerooutput power, in case the panel WD TX chain is turned off). This cancause the WD to lose UL coverage (UL coverage is expected to be verychallenging for higher frequencies) that might lead to a radio linkfailure.

Accordingly, instead of calculating the final RSRP in thestraightforward fashion, the WD may take the information about availableoutput power for the different antenna arrangement attained in step s502into account when calculating the final RSRP value. This could be doneby weighting the individual RSRP values for the two WD antennaarrangements unequally when calculating the final RSRP value.

For example, in one scenario, the lower the available output power isfor a certain WD antenna arrangement, the RSRP value for that antenna isweighted lower when calculating the final RSRP. For instance, assumethat for a given TRP TX beam candidate the WD: 1) determines a firstRSRP value (RSRP-1) based on the CSI-RS that was transmitted using thegiven TRP TX beam candidate and received using the first antennaarrangement and 2) determines a second RSRP value (RSRP-2) based on theCSI-RS that was transmitted using the given TRP TX beam candidate andreceived using the second antenna arrangement. In this scenario, thefinal RSRP (RSRP-Final) value for the given candidate TRP TX beam may becalculated as follows: RSRP−Final=W1*RSRP−1+W2*RSRP−2, where W1+W2=1 andW1 and W2 are a function of TP1 and TP2. For instance, W1=(TP1/TP2)×W2for TP2>0.

In an extreme case where the available output power of an antennaarrangement is zero (e.g., TP2=0), the corresponding weight forcalculating the resulting RSRP is also set to zero (e.g., if TP2=0, thenW2 is set to 0), such that the resulting RSRP will only be calculatedbased on RSRP from the other antenna arrangement at the WD. This impliesthat the WD selects the preferred DL beam taking into account bothexpected UL and expected DL performance. In some embodiments, such aweighting scheme is only applied when the WD knows that the UL beamselection will be implicitly determined by the DL beam selection, whichthe WD may know from a Radio Resource Control (RRC) configurationtransmitted to the WD.

In yet another embodiment the WD 502 takes an estimate UL link budgetinto account when determining the RSRP weights (e.g., W1 and W2) for thedifferent antenna arrangements during a P2 beam sweep. The UL linkbudget could for example be estimated based on DL RS signals used for ULpower control. In case the estimated link budget is very poor such thatthe WD is far from being able to apply the desired output power neededfor reaching the open loop power control goal of x dB SINR, the WDshould put larger weight on the RSRP calculated on antenna arrangementswith higher available WD output power, since otherwise there is a riskthat the WD will lose the UL coverage which might lead to radio linkfailure.

In yet another embodiment the WD 502 takes its UL buffer status (or someother way to estimate the needed capacity in UL vs DL) in to accountwhen determining the RSRP calculation weights. For example, if the WDhas a lot of data to transmit in UL, the WD should use RSRP weights thatmainly facilitate the UL link, while if the WD has a lot of data toreceive in DL, the WD should not be so aggressive with changing theweights for the RSRP in order to improve the UL.

In step 508, after determining the final RSRP value for each candidateTRP TX beam, WD 502 uses the final RSRP values to select the N bestcandidate TRP TX beams (N>0).

In step 510, the WD reports back the CSI-RS resource indicator(s)(CRI(s)) corresponding to the selected N best TRP TX beam(s). The TRPmay then utilize the beam report for both UL and DL beam selection.

FIG. 7 is a flow chart illustrating a process 700, according to oneembodiment, for selecting candidate TX beams included in a set ofcandidate TX beams including at least a first candidate TX beam b1.Process 700 is performed by WD 502 and may begin in step s702.

Step s702 comprises determining a first uplink transmit power (TP1) forthe first antenna arrangement AA1 and determining a second uplinktransmit power (TP2) for the second antenna arrangement AA2.

Step s704 comprises using the first antenna arrangement to receive areference signal transmitted by a base station (e.g., TRP 504) using thefirst candidate TX beam.

Step s706 comprises obtaining, based on the reference signal transmittedby the base station using the first candidate TX beam and received usingthe first antenna arrangement, a first received reference signal powervalue (P11) associated with the first antenna arrangement.

Step s708 comprises using the second antenna arrangement to receive thereference signal transmitted by the base station using the firstcandidate TX beam.

Step s710 comprises obtaining, based on the reference signal transmittedby the base station using the first candidate TX beam and received usingthe second antenna arrangement, a second received reference signal powervalue (P12) associated with the second antenna arrangement.

Step s712 comprise determining a final reference signal received powervalue (Pn1) for the first candidate TX beam using P11 and P12 andfurther using TP1, TP2, information indicating an amount of data in theuplink transmit buffer, an estimate of an uplink, UL, link budget,and/or information indicating whether or not UL beam selection isdetermined based on DL beam selection.

Step s714 comprises using Pn1 to assign a rank to the first candidate TXbeam.

Step s716 comprises determining, based on the rank assigned to the firstcandidate TX beam, whether or not to include in a beam report a beamindicator (e.g., a CRI) indicating the first candidate TX beam.

Step s718 comprises transmitting the beam report to the base station,wherein the beam report includes at least one beam indicator indicatingat least one candidate TX beam.

In some embodiments, determining Pn1 comprises calculating(W1×P11)+(W2×P12), wherein the values of W1 and W2 are dependent on TP1and TP2, the amount of data in the uplink transmit buffer, the estimateof the UL link budget, and/or information indicating whether or not ULbeam selection is determined based on DL beam selection.

In some embodiments, process 700 may further include: determiningwhether the transmit buffer contains more than a threshold amount ofdata; and setting each of W1 and W2 to a value that is dependent on TP2and TP1 if and only if it is determined that: i) the transmit buffercontains more than a threshold amount of data and ii) the informationindicates that UL beam selection is determined based on DL beamselection, otherwise setting W1 and W2 to default values (e.g. W1 and W2are both set to a default value of 0.5).

In some embodiments, process 700 may also include determining that thetransmit buffer contains less than a threshold amount of data; andsetting W1 and W2 equal to 0.5 as a result of determining that thetransmit buffer contain less than the threshold amount of data.

In some embodiments, W1+W2=1, W2=((TP2/TP1)+A+B)×W1, A is a value thatis dependent on the amount of data in the uplink buffer, and B is avalue that is dependent on the estimate of the UL link budget. In someembodiments, A=B=0.

In some embodiments, process 700 may also include receiving a messagecomprising the information indicating whether or not UL beam selectionis determined based DL beam selection; determining that the informationindicates that UL beam selection is not determined based DL beamselection; and as a result of determining that the information indicatesthat UL beam selection is not determined based DL beam selection,setting W1 to a default value and setting W2 to a default value.

In some embodiments, process 700 may also include using the firstantenna arrangement to receive a reference signal transmitted by thebase station using a second candidate TX beam; obtaining, based on thereference signal transmitted by the base station using the secondcandidate TX beam and received using the first antenna arrangement, athird received reference signal power value, P21, associated with thefirst antenna arrangement; using the second antenna arrangement toreceive the reference signal transmitted by the base station using thesecond candidate TX beam; obtaining, based on the reference signaltransmitted by the base station using the second candidate TX beam andreceived using the second antenna arrangement, a fourth receivedreference signal power value, P22, associated with the second antennaarrangement; determining a final reference signal received power value,Pn2, for the second candidate TX beam using P21 and P22 and furtherusing TP1, TP2, information indicating the amount of data in the uplinktransmit buffer, and/or the estimate of the UL link budget; using Pn2 toassign a rank to the second candidate TX beam; and determining, based onthe rank assigned to the second candidate TX beam, whether or not toinclude in the beam report a beam indicator indicating the secondcandidate TX beam. In some embodiments, determining, based on the rankassigned to the second candidate TX beam, whether or not to include inthe beam report a beam indicator indicating the second candidate TX beamcomprises determining whether Pn2 is larger than Pn1. In someembodiments, process 700 may also include including in the beam report areference signal resource index (e.g., a CRI) corresponding to thesecond candidate TX beam as a result of determining that Pn2 is largerthan Pn1.

FIG. 8 is a block diagram of WD 502, according to some embodiments. Asshown in FIG. 8, WD 502 may comprise: processing circuitry (PC) 802,which may include one or more processors (P) 855 (e.g., one or moregeneral purpose microprocessors and/or one or more other processors,such as an application specific integrated circuit (ASIC),field-programmable gate arrays (FPGAs), and the like); communicationcircuitry 848 coupled to a first antenna arrangement 849 and a secondantenna arrangement 846 and comprising a transmitter (Tx) 845 and areceiver (Rx) 847 for enabling WD 502 to transmit data and receive data(e.g., wirelessly transmit/receive data); and a local storage unit(a.k.a., “data storage system”) 808 which may include one or morenon-volatile storage devices and/or one or more volatile storagedevices. As shown in FIG. 8, buffer 612 may be a component of the localstorage unit 808. In embodiments where PC 802 includes a programmableprocessor, a computer program product (CPP) 841 may be provided. CPP 841includes a computer readable medium (CRM) 842 storing a computer program(CP) 843 comprising computer readable instructions (CRI) 844. CRM 842may be a non-transitory computer readable medium, such as, magneticmedia (e.g., a hard disk), optical media, memory devices (e.g., randomaccess memory, flash memory), and the like. In some embodiments, the CRI844 of computer program 843 is configured such that when executed by PC802, the CRI causes WD 502 to perform steps described herein (e.g.,steps described herein with reference to the flow charts). In otherembodiments, WD 502 may be configured to perform steps described hereinwithout the need for code. That is, for example, PC 802 may consistmerely of one or more ASICs. Hence, the features of the embodimentsdescribed herein may be implemented in hardware and/or software.

While various embodiments are described herein (including the Appendix,if any), it should be understood that they have been presented by way ofexample only, and not limitation. Thus, the breadth and scope of thisdisclosure should not be limited by any of the above-described exemplaryembodiments. Moreover, any combination of the above-described elementsin all possible variations thereof is encompassed by the disclosureunless otherwise indicated herein or otherwise clearly contradicted bycontext.

Additionally, while the processes described above and illustrated in thedrawings are shown as a sequence of steps, this was done solely for thesake of illustration. Accordingly, it is contemplated that some stepsmay be added, some steps may be omitted, the order of the steps may bere-arranged, and some steps may be performed in parallel.

1. A method for selecting candidate transmit (TX) beams included in aset of candidate TX beams including at least a first candidate TX beam,wherein the method is performed by a wireless device, and wherein thewireless device comprises an uplink transmit buffer for storing data fortransmission and a plurality of antenna arrangements, including a firstantenna arrangement and a second antenna arrangement, the methodcomprising: determining a first uplink transmit power, TP1, for thefirst antenna arrangement; determining a second uplink transmit power,TP2, for the second antenna arrangement; using the first antennaarrangement to receive a reference signal transmitted using the firstcandidate TX beam; obtaining, based on the reference signal transmittedusing the first candidate TX beam and received using the first antennaarrangement, a first received reference signal power value, P11,associated with the first antenna arrangement; using the second antennaarrangement to receive the reference signal transmitted using the firstcandidate TX beam; obtaining, based on the reference signal transmittedusing the first candidate TX beam and received using the second antennaarrangement, a second received reference signal power value, P12,associated with the second antenna arrangement; determining a firstfinal reference signal received power value, Pn1, for the firstcandidate TX beam using P11 and P12 and further using one or anycombination of: TP1, TP2, information indicating an amount of data inthe uplink transmit buffer, an estimate of an uplink (UL) link budget,or information indicating whether or not UL beam selection is determinedbased on DL beam selection; determining, based on Pn1, whether or not toinclude in a beam report a beam indicator indicating the first candidateTX beam; and transmitting the beam report to the base station, whereinthe beam report includes at least one beam indicator indicating at leastone candidate TX beam.
 2. The method of claim 1, wherein determining Pn1comprises calculating Pn1=(W1×P11)+(W2×P12), wherein the values of W1and W2 are dependent on TP1 and TP2, the amount of data in the uplinktransmit buffer, the estimate of the UL link budget, and/or informationindicating whether or not UL beam selection is determined based on DLbeam selection.
 3. The method of claim 2, further comprising:determining whether the transmit buffer contains more than a thresholdamount of data; and setting each of W1 and W2 to a value that isdependent on TP2 and TP1 if and only if it is determined that: i) thetransmit buffer contains more than a threshold amount of data and ii)the information indicates that UL beam selection is determined based onDL beam selection, otherwise setting W1 and W2 to default values.
 4. Themethod of claim 2, further comprising: determining that the transmitbuffer contains less than a threshold amount of data; and setting W1 andW2 equal to 0.5 as a result of determining that the transmit buffercontain less than the threshold amount of data.
 5. The method of claim2, wherein: W1 + W2 = 1, W2 = ((TP 2/TP1) + A + B) × W 1, A is a valuethat is dependent on the amount of data in the uplink buffer, and B is avalue that is dependent on the estimate of the UL link budget.
 6. Themethod of claim 5, wherein A=B=0.
 7. The method of claim 1, furthercomprising receiving a message comprising the information indicatingwhether or not UL beam selection is determined based on DL beamselection; determining that the information indicates that UL beamselection is not determined based on DL beam selection; and as a resultof determining that the information indicates that UL beam selection isnot determined based on DL beam selection, setting W1 to a default valueand setting W2 to the default value or another default value.
 8. Themethod of claim 1, further comprising: using the first antennaarrangement to receive a reference signal transmitted by the basestation using a second candidate TX beam; obtaining, based on thereference signal transmitted by the base station using the secondcandidate TX beam and received using the first antenna arrangement, athird received reference signal power value, P21, associated with thefirst antenna arrangement; using the second antenna arrangement toreceive the reference signal transmitted by the base station using thesecond candidate TX beam; obtaining, based on the reference signaltransmitted by the base station using the second candidate TX beam andreceived using the second antenna arrangement, a fourth receivedreference signal power value, P22, associated with the second antennaarrangement; determining a final reference signal received power value,Pn2, for the second candidate TX beam using P21 and P22 and furtherusing TP1, TP2, information indicating the amount of data in the uplinktransmit buffer, and/or the estimate of the UL link budget; anddetermining, based on Pn2, whether or not to include in the beam reporta beam indicator indicating the second candidate TX beam.
 9. The methodof claim 8, wherein determining, based on Pn2, whether or not to includein the beam report a beam indicator indicating the second candidate TXbeam comprises determining whether Pn2 is larger than Pn1.
 10. Themethod of claim 9, further comprising including in the beam report areference signal resource index corresponding to the second candidate TXbeam as a result of determining that Pn2 is larger than Pn1.
 11. Awireless device (WD), the WD comprising: an uplink transmit buffer; afirst antenna arrangement; and a second antenna arrangement, wherein thewireless device is configured to perform a process that comprises:determining a first uplink transmit power, TP1, for the first antennaarrangement; determining a second uplink transmit power, TP2, for thesecond antenna arrangement; using the first antenna arrangement toreceive a reference signal transmitted by a base station using the firstcandidate TX beam; obtaining, based on the reference signal transmittedby the base station using the first candidate TX beam and received usingthe first antenna arrangement, a first received reference signal powervalue, P11, associated with the first antenna arrangement; using thesecond antenna arrangement to receive the reference signal transmittedby the base station using the first candidate TX beam; obtaining, basedon the reference signal transmitted by the base station using the firstcandidate TX beam and received using the second antenna arrangement, asecond received reference signal power value, P12, associated with thesecond antenna arrangement; determining a final reference signalreceived power value, Pn1, for the first candidate TX beam using P11 andP12 and further using TP1, TP2, information indicating an amount of datain the uplink transmit buffer, an estimate of an uplink, UL, linkbudget, and/or information indicating whether or not UL beam selectionis determined based on DL beam selection; determining, based on Pn1,whether or not to include in a beam report a beam indicator indicatingthe first candidate TX beam; and transmitting the beam report to thebase station, wherein the beam report includes at least one beamindicator indicating at least one candidate TX beam.
 12. The WD of claim11, wherein the UE is configured to determine Pn1 by calculatingPn1=(W1×P11)+(W2×P12), wherein the values of W1 and W2 are dependent onTP1 and TP2, the amount of data in the uplink transmit buffer, theestimate of the UL link budget, and/or information indicating whether ornot UL beam selection is determined based on DL beam selection.
 13. TheWD of claim 12, wherein the WD is further adapted to: determine whetherthe transmit buffer contains more than a threshold amount of data; andset each of W1 and W2 to a value that is dependent on TP2 and TP1 if andonly if it is determined that: i) the transmit buffer contains more thana threshold amount of data and ii) the information indicates that ULbeam selection is determined based on DL beam selection, otherwisesetting W1 and W2 to default values.
 14. The WD of claim 12, wherein theWD is further configured to: determine whether the transmit buffercontains less than a threshold amount of data; and set W1 and W2 equalto a predetermined value as a result of determining that the transmitbuffer contains less than the threshold amount of data.
 15. The WD ofclaim 12, wherein W 1 + W 2 = 1, W2 = ((TP 2/TP1) + A + B) × W 1, A is avalue that is dependent on the amount of data in the uplink buffer, andB is a value that is dependent on the estimate of the UL link budget.16. The WD of claim 15, wherein A=B=0.
 17. The WD of claim 11, whereinthe WD is further configured to: determine, based on informationincluded in a received message, whether UL beam selection is notdetermined based on DL beam selection; and as a result of determiningthat UL beam selection is not determined based on DL beam selection, setW1 to a default value and set W2 to the default value or another defaultvalue.
 18. The WD of claim 11, wherein the WD is further configured to:use the first antenna arrangement to receive a reference signaltransmitted by the base station using a second candidate TX beam;obtain, based on the reference signal transmitted by the base stationusing the second candidate TX beam and received using the first antennaarrangement, a third received reference signal power value, P21,associated with the first antenna arrangement; use the second antennaarrangement to receive the reference signal transmitted by the basestation using the second candidate TX beam; obtain, based on thereference signal transmitted by the base station using the secondcandidate TX beam and received using the second antenna arrangement, afourth received reference signal power value, P22, associated with thesecond antenna arrangement; determine a final reference signal receivedpower value, Pn2, for the second candidate TX beam using P21 and P22 andfurther using TP1, TP2, information indicating the amount of data in theuplink transmit buffer, and/or the estimate of the UL link budget; anddetermine, based on Pn2, whether or not to include in the beam report abeam indicator indicating the second candidate TX beam.
 19. The WD ofclaim 18, wherein the WD is configured to determine whether or not toinclude in the beam report the beam indicator indicating the secondcandidate TX beam by performing a process that includes comparing Pn2with Pn1.
 20. A computer program product comprising a non-transitorycomputer readable medium storing a computer program comprisinginstructions for adapting an apparatus to perform the method of claim 1.